In Long Time Evolution (LTE) Release 9 of 3rd Generation Partnership Project (3GPP), an enhanced Multimedia Broadcast Multicast Service (eMBMS) can be transmitted in a multi-cell mode, i.e. a so-called Multicast/Broadcast over Single Frequency Network (MBSFN) mode. In this way, the data can be transmitted simultaneously by adopting the same modulation and coding scheme in multiple cells on the same physical resources. A terminal can merge signals received from different cells, and the frame structure of transmitting the signal is shown in FIG. 1. A terminal which supports the eMBMS can receive the same eMBMS received from multiple cells at the relay node, and the multiple received eMBMSs will not interfere with each other.
In LTE Release10, a Relay Node (RN) is introduced into the network as an important means for expanding system coverage and improving system capacity. In the Release10 network, the RN is similar to a base station which has an independent Physical Cell ID. Therefore, its network deployment scenario is similar to a pico cell, and a schematic diagram of the specific network architecture is shown in FIG. 2.
In the prior art, the RN communicates with its subordinate terminal in a unicast mode. If the RN does not support the MBSFN transmission and transmits unicast data in an MBSFN sub-frame structure shown in FIG. 1, the terminal which supports eMBMS will receive the unicast data sent from the relay node under the relay node, rather than the corresponding eMBMS data. Moreover, the received unicast service will be interfered greatly due to the impact of eMBMSs transmitted from other cells.
In addition, the MBMS Control Channel (MCCH) is a point-to-multipoint downlink channel in the LTE MBMS system, which is used to transmit control information from the network side to the User Equipment (UE) side. The network side indicates position information of the MCCH to the UE in a Broadcast Control Channel (BCCH), thus allowing the user equipment to read information transmitted on the MCCH according to the indicated position.
The information transmitted on the MCCH usually includes LTE MBMS information and relevant information of the radio resource allocation, where:
the MBMS information is adapted to indicate MBMSs available in a cell. For each service, it may include some information, such as, a service identifier (service ID), a session identifier (session ID);
the relevant information of the radio resource allocation refers to information about radio resource used in a cell which uses one or more MBMS service descriptions. For each service, the relevant information may include some information, such as, information of physical channel occupied by a service, transmission channel information.
When the information carried by the MCCH changes, for example the MBMS service changes, or session or radio carrying information changes, the network side needs to notify the user equipment, that is, the network side needs to send an MCCH modification notification to the user equipment. After receiving the MCCH modification notification, the user equipment will listen the MCCH to acquire new information changed.
However, in the LTE Release10, a problem to be solved is to eliminate the impact of introduction of the RN on the reception of the MBMS of the UE in the network in which the RN is introduced and to receive the MCCH modification notification timely, and those problems have no appropriate solution at present.